By default, an Tree uses the same font as its parent widget
Tree.font read/write property
Get the Tree font, a string value that represent the font name.
To set the Tree.font property, you can assign a string that represent either a font name of an installed system font, or a font file (*.ttf, *.fon...). A File can also be provided, representing a font file.
Note that only the font family is changed. The font style and font size are not affected (see the Tree.fontstyle and the Tree.fontsize properties).
Example
local ui = require "ui"
-- create a simple Window
local win = ui.Window("Tree.font sample", 320, 200)
local tree = ui.Tree(win, {"Item 1", "Item 2", "Item 3"}, 106, 20)
tree.font = "Fixedsys"
win:show()
-- update the user interface until the user closes the Window
repeat
ui.update()
until not win.visible